Atmospheric carbon growth accelerates
The rise in human carbon emissions increased sharply in recent years, scientists from a global climate research network have found.
While in 2000 global carbon emissions were rising at 1% per year, this rate went up sharply to reach an annual 2.5% in 2005, Australian scientists participating in the Global Carbon Project said.
The rise has led to a global total of 7.9bn tonnes of CO2 being released into the atmosphere in 2005, up from 6.8bn tonnes in 2000, said Dr Mike Raupach of Australian research institution CSIRO.
“From 2000 to 2005, the growth rate of carbon dioxide emissions was more than 2.5 percent per year, whereas in the 1990s it was less than one percent per year,” he said.
The findings, which echo recent results from the World Meteorological Organisation, could impact predictions of temperature rise.
“Recent emissions seem to be near the high end of the fossil fuel use scenarios used by the Intergovernmental Panel on Climate Change,” said Dr Raupach.
This would imply that the resulting temperature rise would also be at the high end of the predicted range of 1.4 – 5.8 degrees C, although other greenhouse gases, which account for about 40% of the greenhouse effect, must also be considered.
The way that soils, seas and ecosystems take up CO2 may also change with rising atmospheric concentrations, but the findings signal that efforts to curb climate change are stalling, at least on a global scale.
“On our current path, it will be difficult to rein in carbon emissions enough to stabilize the atmospheric carbon dioxide concentration at 450 ppm,” said Dr Raupach.
The accelerating rise in emissions is thought to stem from more coal being burnt worldwide as oil becomes more expensive, as well as the advance in energy efficiency slowing down.
The Global Carbon Project is an international network of climate scientists that aims to establish a “common, mutually agreed knowledge base supporting policy debate and action to slow the rate of increase of greenhouse gases in the atmosphere.”
More information on the Global Carbon Project can be found here.